1. Field of the Invention
The present invention relates to a method and apparatus for warning a vehicle driver of a potentially dangerous road surface.
2. Description of Related Art
A good road surface in the context of the present invention is one that has good- frictional characteristics with the rubbers of tire treads and furthermore one which has consistent or unvarying frictional characteristics over its surface
In contrast a poor road surface is one which has inconsistent or varying frictional characteristics having areas of lower friction such as may be due to a variable composition or loose surface or the presence of pools of water, patches of mud or ice or spillages of oil. Under many conditions such as in the dark or in the presence of black ice drivers may be completely ignorant of the quality of the road surface on which they are travelling. Such poor road surfaces are potentially hazardous for drivers in that they may present different levels of friction to different wheels of the vehicle rendering the response of the vehicle unpredictable.